I'm getting kicked out! What am I going to do?

I'm 24 years old and I'm getting kicked out of my house, My mom says I have to be out by the end of next week because that's when my sister's bratty son is coming. I've hated living here ever since my sister came back to live with us and she immediately wanted her old bedroom back although she hadn't lived here in years and I was using her old room as my art studio and she immediately told me I needed to get my "junk" out of her room! But it's not junk to me they are my paintings that I worked very hard on! And my mom agreed with her and my work is now in the garage and I don't have a studio anymore. Now, she's kicking me out completely for my sister's son! I only work as a waitress and hardly make any money. This guy I work with said I can stay with him but I'm not sure I know him but he's not really a friend. What should I do?